Microsoft Creates Half-Electron Quasiparticle for Its Future Quantum Computer

gizmodo.com

3 points·grokys··3 comments

They didn't create "half-electron". They created Majorana quasiparticles inside a superconductor.

Majorana particles are weird because they are their own antiparticle, but they are not "half-electrons". Moreover, probably neutrinos are Majorana particles, but nobody is sure, and currently there are some experiments to try to prove it.

Any Dirac 4-spinor can be formally decomposed into two independent Majorana spinors, so yes a Majorana spinor May be thought of as half of a conventional Dirac spinor.

On a 1D lattice this manifests itself in that one can formally decompose each electron on the chain into two Majorana spinors.

This is a trivial relabelling if degrees of freedom in the bulk of the lattice, however it reveals the possibility of topologically distinct states on the boundaries of the lattice by leaving dangling bonds on the edge.

But the two Majorana particles in the decomposition are the Majorana particles they are measuring, or they are different? In particular, if they join two of the Majorana particles they are measuring, can they form an electron or they get something bigger?

[This is a tricky question, because the "electrons" in a crystal are not exactly the electrons in vacuum, for example they have a different effective mass.]

Also, can they measure the charge of the Majorana particles using the Hall effect or something, or trying to measure the charge destroy the quasiparticle?

Reply on news.ycombinator.com